Setup; Operation - Analog Devices ADPA1107-EVALZ User Manual

ADPA1107-EVALZ

SETUP

The connections required to use the ADPA1107-EVALZ with
the drain bias pulser board are shown in Figure 5. Before applying
any bias or signals, plug the pulser board into the ADPA1107-
EVALZ so that the P1 header connector of the pulser board
connects to the J3 header of the ADPA1107-EVALZ, and the
pulser board P2 header connects to the J4 header of the
ADPA1107-EVALZ. All external supply voltages and control
signals are applied to the pulser board through the J1 through
J4 connectors, which are listed in Table 3.
The gate control voltage applied to the J4 connector, passes
directly through the pulser board and drives the VGG1 pin of
the ADPA1107. Because the VDD and GND lines carry
currents up to 2 A, the use of heavy gauge twisted pair wires is
recommended to minimize voltage drops. To observe the pulsed
drain voltage (PULSED_VDD) that drives the VDDxA/VDDxB
pins of the ADPA1107, connect an oscilloscope to the J5 coaxial
connector on the pulser board.
Connect a digital pulse generator that can generate 0 V to 5 V
pulses with a pulse width of 100 μs and a duty cycle of 10% to the J4
connector.
User Guide
To observe and measure the drain current and the RF output
power of the ADPA1107, use a current probe and a pulsed RF
power meter. If these methods are not available, make
approximations as described in the Making Average to Pulsed
Approximations section.

OPERATION

Take the following steps to power-up (unless otherwise stated,
all signals are applied to the pulser board):
1. Set the voltage on the J4 connector, PULSE, to 0 V.
2. Set the voltage on the J3 connector, VG1, to −4 V.
3. Set the voltage on the J1 connector, VDD, to 28 V.
4. Turn on the J4 connector, PULSE (0 V/5 V, 100 μs, 10%
duty cycle).
5. Increase the voltage on the J3 connector, VG1, (nominally
−2.6 V) until the target I
6. Apply the RF input signal to the RFIN connector of the
ADPA1107-EVALZ.
Take the following steps to power-down:
1. Turn off the RF input signal.
2. Set the voltage on the J3 connector, VG1, to −4 V.
3. Turn off the J4 connector, PULSE (set to 0 V).
4. Set the voltage on the J1 connector, VDD, to 0 V.
5. Set the voltage on the J3 connector, VG1, to 0 V.
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UG-1962
is reached (nominally 350 mA).
DQ